How can I solve the C2400 error in visual studio with a variable called ptr?

Question

I am programming in c++ with x86 assembly integrated with block _asm {} but I keep running into the same error C2400. I’m trying to calculate the first n prime numbers.

Error: Error C2400 assembly code syntax error inserted in 'second operand'; found 'PTR'

The problem is on line 2.

void primosx86(int n, vector<int>& primos) {
    primos.resize(n);               
    int* ptr = primos.data();       

    __asm {
        mov ecx, n
        lea edi, [ptr]
        mov edi, [edi]
        mov esi, 2
        outer_loop:
        mov eax, esi
            mov ebx, 2
            inner_loop :
            cmp ebx, eax
            jge is_prime
            mov edx, 0
            div ebx
            cmp edx, 0
            je not_prime
            inc ebx
            jmp inner_loop

            is_prime :
        mov[edi], eax
            add edi, 4
            dec ecx
            jz finished
            not_prime :
        inc esi
            jmp outer_loop

            finished :

    }
}

I asked chatGPT, but even though it suggested modifications to the code, I ended up in the same place and receiving the same error.

Answer 1

PTR is a reserved word in MASM. Pick a different name for your variable.